SU1527159A1 - Method of producing granulated potassium chloride - Google Patents

Abstract

The invention relates to the technology of obtaining granulated potassium chloride from the initial wet crystalline material and contributes to an increase in the yield of marketable product, increasing the strength of the granules while reducing energy consumption. According to the proposed method, the crystalline wet material is pre-mixed with a hot dried returum, taken in an amount of 60-160% by weight of the starting material, and mixing is carried out until the mixture reaches a temperature of 45 to 59 ° C and a humidity of 5 to 2.5% . The resulting mass is subjected to drying, pressing granulation, followed by crushing the resulting tape, classifying the formed particles and feeding part of the retour to the process head. The invention allows to reduce energy consumption by 10-15%, to increase the yield of the conditioned product by 8-10%, to improve the quality of the finished product, to increase the strength of the granules from 50-60 to 70-90%. 1 tab.

Description

The invention relates to a process for the production of granulated potassium chloride from a starting wet crystalline material.

The purpose of the invention is to increase the yield of the commercial product and increase the strength of the granules while reducing energy consumption.

Example (known). The initial product with a moisture content of 6% and a flow rate of 60. kg / h is fed to a drum dryer on a dry product, where it is dried to a moisture content of 1%. Then the product enters the KS furnace, where it is dried to a moisture content of 0.3% and, together with 200% retour by weight of the starting product (120 kg / h), is mixed and heated before and then fed to a roll press. After pressing on a rotary crusher and classifying on a vibrating screen, 60 kg / h of a marketable product is obtained. In this case, the formed retur in an amount of 300% by weight of the starting material (180 kg / h) is divided into two parts. One of the parts, 120 kg / h (200%), goes into the furnace not for heating and displacement with the starting material, but the second, 60 kg / h (100%), goes for repeated pressing without intermediate heating. The load on the roller press is 240 kg / h.

SP

ND

SP

0

The strength of the granules determined by the standard procedure is 58%.

Examples 2-6. The tests are carried out on the same installation according to the proposed method.

The process consists of the following stages: CMemeAie of the initial product with a part of the retour in the mixer of the continuous action of the screw type, drying and heating the mixture in the KS furnace, pressing on a smooth-roll press, crushing on a rotary crusher, classification, returning a part of the petypa with the original product, and the rest of the retour is re-pressed

The test results are given in the table,

As can be seen from the above examples, when part of the retour is supplied in an amount of 60-160% by weight of the raw material, there is an increase in the productivity of the process for a commercial product by 8-10% with a simultaneous increase in the strength of the granules to 70-90%, with more than 160% by weight of the starting material an increase in the yield of the finished product and an improvement in its quality are not observed.

When applying for mixing a hot product in an amount of less than 60% by weight of the starting material, a significant part of the wet starting material does not contact with the hot particles of the retur and does not form agglomerates in the mixing zone. In addition, not enough heat is introduced with the retur to evaporate moisture at the points of contact, to warm the mixture of material and the vapor-gas mixture between the particles of the material, which prevents the formation of crystalline bonds — bridges between the crystals. However, the main part of the retur does not undergo agglomeration before pressing, and therefore, its functional composition has not improved.

If mixing is carried out in hot mix, in excess of

0

five

about 5

160% of the mass of the source material, there is a rapid dehydration of the mixture at the initial stages of mixing not only at local points of contact, but also from the entire surface of the particles, and consequently, the possibility of secondary condensation at the final stage of the mixing process appears. In addition, the starting material particles are not enough to evenly cover the entire surface of the retur particles, which leads to a decrease in the number of jumper bonds and, consequently, to a decrease in the average size of the agglomerates and their strength.

The proposed method allows to reduce energy consumption by 10-15%, increase the yield of the conditioned product by 8-10%, improve the quality of the finished product (increase the strength of the granules from 50-60 to 70-90%) by conducting agglomeration of hot dry oil with wet cold starting product with the formation of crystalline bonds of the jumpers in the process of mixing before drying and hardening them at the stage of the substance.

about . 25

Claims (1)

3Q claims The method of obtaining granulated potassium chloride from a fine crystalline wet material, including drying it, followed by pressing, crushing the resulting tape, classifying the formed particles and feeding part of the retur to the process head, characterized in that, in order to increase the yield of the marketable product and increase the strength of the granules while reducing energy consumption, fine-crystalline cold and wet raw materials before drying are mixed with a hot dried retur, taken in the amount of 60-160% of m Raw materials and mixing are carried out until the mixture reaches a temperature of 45 to a moisture content of 5 to 2.5%. 50 60 100 160 180 240 230 225 235 240 39,8 45.6 53 58.9 78.1 60 64.9 66.6 65.3 60 60 72 88 76 62 ABOUT 8.1 II 8.6 ABOUT